Packaging System and Method

ABSTRACT

A package for an article comprises a pressurised outer bag having gas-tight seals at opposite ends, and an inner web for supporting the article within the outer bag. The web extends along the length of the outer bag and is secured to the outer bag only at the gas-tight seals. The web is maintained under sufficient tension by the pressure within the outer bag to suspend the article within the bag and to maintain a space between the article and the outer bag on all sides of the article.

FIELD OF THE INVENTION

This invention concerns a flexible package that may be used forpackaging solid or liquid products and may be manufactured on automatedproduction machinery.

BACKGROUND OF THE INVENTION

Packaging of products serves several functions, including protecting thecontained item from contamination or deterioration, and minimisingmechanical damage during handling or transport.

Packaged items are often sealed within a pouch, for example a vacuumpack or a blister pack. However, depending on the packaging material,such sealed pouches may not provide sufficient mechanical protection.Conventionally, this problem is addressed by increasing the thickness orrigidity of the sealed pouch. Additionally or alternatively, the sealedpouch may be cushioned by surrounding material, such as bubble wrap,corrugated card or expanded foam material, for example.

However, these and other methods of protection tend to increase the bulkor weight of the package or a consignment of packages, and therebyincrease costs and waste along the supply chain.

SUMMARY OF THE INVENTION

In accordance with a first aspect of the invention, there is provided apackage for an article comprising a pressurised outer bag havinggas-tight seals at opposite ends, and an inner web for supporting thearticle within the outer bag, wherein the web extends along the lengthof the outer bag and is secured to the outer bag only at the gas-tightseals, and wherein the web is maintained under sufficient tension by thepressure within the outer bag to suspend the article within the bag andto maintain a space between the article and the outer bag on all sidesof the article.

In the invention, the packaged articled is held in suspension within asealed inflated bag and is in this way protected against mechanicalimpact.

In a preferred embodiment of the invention, the inner web is wrappedaround the article and sealed to form an inner pouch within the outerbag. By providing an inner pouch within the outer protective bag, thisembodiment of the invention can be used to package liquids as well assolid articles. A further advantage of such an embodiment of theinvention is that the pouch may be evacuated or filled with an inert gasor gaseous mixture, as may be desirable to prolong the shelf life ofcertain articles such as foodstuffs.

The outer bag may itself be pressurised with an inert gas or gaseousmixture.

An outer bag formed from a flat sheet that is drawn from a reel and madeinto a tubular sleeve by means of a hermetic back seal will be generallypillow shaped with a rounded cross section, but to improve thestackability of packages and offer additional protection, the outer bagmay include longitudinally extending welded pinches to impart a cuspedcross section to the outer bag.

Embodiments of the invention can thus be seen to provide an integratedpack that protects and cushions a product, while reducing extraneouspackaging material. The pack can be produced on a range of automaticpackaging machinery or from pre-made pouches.

According to two further aspects, the invention provides a method as setforth in claim 6 of the appended claims and a packaging machine as setforth in claim 12 of the appended claims.

The term “pouch” as used herein is intended to include any receptacle,cavity or wrapping surrounding and containing a liquid or solid item.

Especially when a number of packages are produced on automated orsemi-automated machinery, those portions of the pouch adhering to theouter bag are sealed thereto in substantially the same manner as thepouch is sealed. Ideally, each sealed portion comprises substantiallythe whole of the relevant edge of the inner pouch. By “seal” is meantsubstantial integration of the material or materials contacting eachother. Depending on the package requirements, all seals should besubstantially hermetic, at least for the expected lifetime of thepackage.

In accordance with known practice, the inner web may be a pouchcontaining a vacuum. Depending on the degree of evacuation required,this may be a hard or soft vacuum. Conveniently, the pouch may beflushed with an inert gas or mixture of inert gases before sealing toensure that any residual gas within the inner pouch is modified to besubstantially unreactive in relation to the contents of the inner pouch,at least for the expected lifetime of the package. Preferably, theresidual gas is substantially oxygen-free.

The outer bag may be pressurised with air or any inert gas or mixture ofgases. Carbon dioxide and nitrogen are convenient and readily available.

The inner web or pouch and the outer bag may be made of the same ordifferent materials, provided that they can be sealed or otherwiseadhere to each other. The inner pouch and the outer bag may besubstantially gas tight, taking account of the applicable pressuredifferentials.

Materials to produce both the inner web/pouch and outer bag can each betailored to the varied requirements of the products contained. To this,a wide range of flexible packaging materials may be utilised. Examplesof suitable materials are:

1. Recyclable materials such as Mono or co-extruded Polyethylene- andMono Polypropylene-based flexible materials.

2. Co-extrusions of (for example)Polyethylene/Nylon/Polyethylene, whereoxygen barriers may be incorporated in the co-extrusion.

3. Two layer laminates of Oriented Polypropylene/modified Polyethylene(sealing compatible to the OPP).

4. Three or more layer laminates of (for example) Polyethylene/Polyester/Polyethylene.

Embodiments of the invention may allow the potential replacement ofseveral current packaging systems offering product protection methodsthat are more energy hungry in their construction and manufacture. Thepackage uses air or an inert gas as the protective medium rather thanrigid or semi-rigid constructions such as: blister pack materials(amorphous polyethylene terephthalate, polyvinyl chloride etc);polystyrene; carton and corrugated board; or cellulose acetatepropionate food packs ((amorphous) polyethylene terephthalate/polyethylene). The invention may thus be environmentally friendly.

The invention allows lower weight flexible packaging materials to betailored to the exact oxygen and barrier requirements of the product. Itmay be possible to enable significant reductions in the total weight ofpackaging material required and in the carbon footprint resource.

The invention also offers the potential to use recycled materials in itsconstruction and to use recyclable materials to pack many non-oxygensensitive products.

Some embodiments of the invention may enable continuous assembly ofpackages by modifying existing machines.

The description below relates to a preferred embodiment in which theinner web is formed as a sealed inner pouch.

When produced in Horizontal Form Fill & Seal form, the package isproduced by folding a flexible material around a product horizontallyand sealing together the two edges of the folded material by means of aback seal, before pulling a soft vacuum around the product if required.The product is then enclosed within the flexible material and end sealsapplied to seal substantially across the axis of the back seal, so thatthe product is gently restrained inside the pouch.

At this point the flexible material is not cut, and the material nowencasing the product continues to a second stage on the machine, where awider material is formed around the inner pouch. A back seal is made tothe outer material before an overpressure of either air or mixed gasesis blown into the package to inflate the outer bag, before end seals areapplied. Only at this stage is the outer bag sealed to the inner pouchand only through the end seals of the outer bag. The inner pouch istherefore held in suspension within the outer bag, protecting it withina cushion of air or mixed gases. The pressure within the outer bagserves to tension the inner pouch suspending the inner pouch clear ofthe walls of the outer bag. The inner pouch may be gas flushed beforesealing, and a mixture of gases may be used to inflate the outer bagwhen a controlled atmosphere is desirable.

When produced in Vertical Form Fill & Seal form, the package is producedby forming a flexible material around a product vertically and sealing aback seal to the material, before pulling a soft or hard vacuum aroundthe product if required. The product is then enclosed within theflexible material and end seals applied so that the product is heldwithin an inner pouch, which may contain a vacuum. At this stage thepouch remains uncut, and the material now encasing the product continuesto the second stage of the machine, where a wider material is formedaround the inner pouch. A back seal is applied to the outer materialbefore an overpressure of either air or mixed gases is blown into thepack to inflate the outer bag before an end seal is applied. The innerpouch is therefore held in suspension within the outer bag, the twopacks being sealed together through the end seals only and with theouter bag protecting the inner pouch within a cushion of air or mixedgases. The inner pack may be gas flushed before sealing, and a mixtureof gases may be used to inflate the outer bag when a controlledatmosphere is desirable

When producing the package in-line from Vacuum Forming machinery, theinner pouch is produced by thermoforming a bottom layer of material in aconventional way, with the product then being inserted into the formedcavity, before a top web of material is sealed to the base web. Ifrequired, a hard or soft vacuum may be pulled around the product in theconventional manner of vacuum forming machinery. The side trims are thenremoved but the end seals are however not cut at this stage. Thematerial encasing the product continues to a second stage on the machineor a second filling machine, where it enters a horizontal form fill andseal section forming a larger outer bag around the inner vacuum-formedpack. A wider material encases this inner pouch and a back seal is madeto the outer material before an overpressure of either air or mixedgases is blown into the pack to inflate the outer bag before the endseals are applied. A mixture of gases may be applied when a controlledatmosphere is desirable. As previously, the inner pouch is held insuspension within the outer bag, the two packs being sealed togetherthrough the end seals only and with the outer bag protecting the innerpouch within a cushion of air or mixed gases.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described further, by way of example, withreference to the accompanying drawings, in which:

FIG. 1 is a drawing of the finished package profile for both horizontaland vertical production methods,

FIG. 2 shows the finished package where the inner pouch is produced froma vacuum forming machine adapted to run in-line through a horizontalform fill and seal machine (see FIG. 7),

FIG. 3 is a drawing of uncut but sealed and vacuumed pouches after thefirst stage of production in both the horizontal form fill and sealversion (see FIG. 5) and the vertical form fill and seal version (seeFIG. 6),

FIG. 4 is a drawing of uncut but sealed and vacuumed pouches after thefirst stage of production in the vacuum forming/Horizontal form fill andseal version (see FIG. 7),

FIG. 5 shows the principle of production using horizontal form fill andseal machinery,

FIG. 6 shows the principle of production using vertical form fill andseal machinery,

FIG. 7 shows as a schematic a machine adaptation wherein a conventionalvacuum forming machine operates in tandem with a horizontal form filland seal machine to produce the package shown in FIG. 2,

FIG. 8 is a transverse section through an alternative packagingembodying the invention,

FIG. 9 shows the packaging of FIG. 8 as viewed from the side, and

FIG. 10 shows a perspective view of the packaging of FIGS. 8 and 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

In FIG. 1, the product to be packaged is designated 1. An inner pouch 2is formed by wrapping an inner web around the product 1, and creating aback seal 3 and inner end seals 4 allowing the product to be gentlyrestrained within the inner pouch and held in a vacuum if required. Anouter material 5 is wrapped around the inner pouch 2 with an overpressure being trapped inside the pack by virtue of a back seal 6 andend seals 7, hermetically sealing the material together. The final packend seal 7 seals the material of the inner pouch 2 to the outer material5, thus allowing the product 1 to be held in suspension within a cushionof air or mixed gases. The region of the end seal 7 designated 8 showsthat the back seals 3 and 6 of the inner pouch 2 and the outer bag 5,are laterally offset from one another to reduce the potential of overpressure loss through pinholing or piping.

In FIG. 2, the product is again designated 1. 21 indicates the innervacuum-formed pack produced from a conventional top and base web withside seals 22 and the end seals 23 applied to the inner pouch 21 toinclude a vacuum, if required, around the product 1 before the sealingis applied. The outer bag inflated with air or a mixture of gases isshown at 5, with the outer horizontal form fill and seal pack beingsealed along a back seal at 6 and the end seals 7 being applied to sealthe outer material. The final pack end seals 7 seal the inner material21 to the outer material 5, thus allowing the product 1 to be held insuspension within a cushion of air or mixed gases.

In FIG. 3, 1 is the product and 2 shows the inner web sealed around theproduct by means of a back seal 3 and end seals 4. The drawing shows thecompleted but uncut inner pack before entering the second stage wherethe outer bag is applied, inflated and sealed.

In FIG. 4, 1 is the product held in a soft or hard vacuum, if required,and sealed within a formed cavity after leaving the vacuum forming stageof providing the first (inner) pouch 21. 41 shows the knives that removethe reel edge trim 42 from both sides of the material. Side seals 22have been made in the machine direction to seal the top web to thebottom web and cross seals 23 have been made to encapsulate the productafter it may have been gas flushed and held in a soft or hard vacuum. 43shows the formed base web cavity around the product, which may have beengas flushed with a mixture of gases if required before vacuuming andsealing the inner pouch 21.

In FIG. 5, 1 is the product on a supporting conveyor (not shown)entering the machine and 2A is the reel of material to form the innerpouch 2. The material is wrapped around the product in the forming box51 and a fin or lap back seal applied by either heated rollers or heatedpads 52 to produce a back seal (see FIG. 3, seal 3). Within this stagethe product may be gas flushed if required before a vacuum, if required,is applied around the product by means of a conventional vacuum lance(not shown) and the end seals 4 formed at a heated station 53. The uncutvacuum packs indicated at 54 then move along a supporting conveyor (notshown) to the secondary forming box 55 where an outer reel of material5A is formed around the inner pack 2. A fin or lap back seal is thenapplied by either heated rollers or heated pads 56 to produce a backseal 6 in any suitable position which seals the outer material 5A onlyto itself. The outer material is not attached to the inner pack. 2Bshows the inner pouch still held in suspension within the outer wrap and5B the outer bag inflated with either air or a mixture of gases, such ascarbon dioxide or nitrogen. The outer bag is then sealed as shown at 57,with the inner and outer bags also being sealed together at 57 beforebeing cut into individual packages. 58 indicates the finished individualpackages leaving the production machine (see also FIG. 1).

In FIG. 6, 1 is the product being dropped vertically. 2A shows a reel ofmaterial to form the inner pouch being formed around a forming collar at61. The material is then pulled or driven by conventional methods, suchas a moving belt or reciprocating jaws 59, with a fin or lap back sealbeing applied at 52. The inner pouch may at this stage be gas flushedwith a mixture of gases before a vacuum is applied around the product,if required, and the pouch is end-sealed at 53. 54 indicates the uncutinner pouches continuing vertically into the second forming collar andtube at 62, where material from reel 5A is formed around the collar 62and pulled or driven down the outer tube, for example by means of amoving belt or reciprocating jaws 63, with a fin or lap back seal beingapplied at 56 in any suitable position. The back seal is applied only tothe outer material, with the inner pouch being in free suspension atthis stage. The outer bag is then inflated with an overpressure ofeither air or a combination of gases, such as carbon dioxide ornitrogen, before the end seals are applied at 57. This sealing stationalso seals the inner pouch to the outer bag before being cut at 57 anddropping onto a supporting conveyor (not shown), with the finishedpackages being indicated at 58 (see also FIG. 1).

In FIG. 7, 1 indicates the product gently restrained or held in a softor hard vacuum after the sealing station on a conventional vacuumforming machine 71 where a base web has been formed to accommodate theproduct and then a top web is sealed to the base web around the product.At vacuum forming machine 71, a top and base web has been used inconventional manner to encase the product with side and end sealssealing the top to the base web around the pouch, that may have been gasflushed with a mixture of gases before sealing. 72 indicates the uncutinner sealed packs continuing on a supporting conveyor 73 beforeentering a horizontal form fill and seal machine, with an outer material5A being formed around the inner pack at forming station 55. A fin orlap back seal 6 is then applied by either heated rollers or heated pads(not shown) to produce a back seal which seals the outer material 5Aonly to itself. The back seal 6 is not attached to the inner pouch. 2Bshows the inner pouch still held in suspension within the outer wrap and5B the outer bag inflated with either air or a mixture of gases, such ascarbon dioxide or nitrogen. The outer bag is then sealed as shown at 57,with the inner and outer bags also being sealed together at 57 beforebeing cut into individual packs. 58 indicates the finished individualpacks leaving the production machine (see also FIG. 2).

An alternative embodiment of the invention is shown in FIGS. 8 and 9,which differs from that shown in FIG. 1 only in that that material ofthe outer bag 5 is pinched at four locations and welded to form fourreinforced lines extending along the length of the outer bag. Because ofthese welded reinforcements, when the bag is inflated, the cross sectionshown in FIG. 8 has four cusps so that the shape of the outer bag is nota smooth ellipse but approximates more to a rectangle. This improves thestackability of the packages.

In FIG. 8, the product 1 is shown in end profile held within the innerpouch 2 which is sealed by a lap or find seam 3. 5 The outer wrap bag 5in this embodiment has four welded pinches which define four cornercusps 80. The outer bag is shown with a back seal 6 of the sameconstruction as described in the previous embodiments but in this caseit is alternatively possible for the seal to acts as, or to beincorporated into, one of the cusps as shown at 6′ in the FIG. 8.

FIG. 9 shows another profile of the same packaging demonstrating themanner in which the product 1 is restrained from moving in the innerpouch 2 by means of the seals 4. FIG. 9 also shows the outer bag 5 withthe pinched longitudinal cusps 80. The outer pack end seals 7 seal thematerial of the outer bag 5 to that of the inner pouch 2 to suspend thearticle 1 in the bag.

FIG. 10 indicates how the inclusion of the cusps 80 approximates theouter pack into more of a rectangular shape.

While the description and drawings relate to the formation of an innerpouch, it should not be considered an essential part of the invention.The essential feature is that the inner web supporting the article orproduct is trapped within the end seals of the outer bag, and maintainedin tension. The tension serves to suspend the inner web (or pouch)relative to the inflated outer bag.

1. A package for an article comprising a pressurised outer bag havinggas-tight seals at opposite ends, and an inner pouch for supporting thearticle within the outer bag, wherein (a) the pouch extends along thelength of the outer bag and is secured to the outer bag only at thegas-tight seals; (b) the pouch is maintained under sufficient tension bygas pressure within the outer bag to suspend the article within the bagand to maintain a space between the article and the outer bag on allsides of the article; and (c) back seals closing the inner pouch and theouter bag respectively are laterally offset from one another.
 2. Apackage as claimed in claim 1, wherein the pouch is evacuated or filledwith an inert gas or gaseous mixture.
 3. A package as claimed in claim2, wherein the outer bag is pressurised with an inert gas or gaseousmixture.
 4. A package as claimed in claim 1, wherein the outer bagincludes longitudinally extending welded pinches to impart a cuspedcross-section to the outer bag.
 5. An assembly comprising a plurality ofpackages as connected end to end to one another, each package comprisinga pressurised outer bag having gas-tight seals at opposite ends, and aninner pouch for supporting the article within the outer bag, wherein (a)the pouch extends along the length of the outer bag and is secured tothe outer bag only at the gas-tight seals; (b) the pouch is maintainedunder sufficient tension by gas pressure within the outer bag to suspendthe article within the bag and to maintain a space between the articleand the outer bag on all sides of the article; and (c) back sealsclosing the inner pouch and the outer bag respectively are laterallyoffset from one another. 6-9. (canceled)
 10. A packaging machine forpackaging a continuous stream of articles, comprising: (i) a firstforming and sealing station at which the articles are supported withinpouches formed at fixed intervals in a longitudinally extending web;(ii) a second forming and sealing station at which the web and thearticles supported thereby are enveloped in a tube; (iii) a source ofpressurised gas for inflating the tube, and (iv) a final sealing stationat which the inflated tube is sealed transversely to the length of theweb and the tube on opposing sides of each article, so as to form asealed outer bag within which an article is packaged; wherein (a) thepressure within the tube serves to tension the web in order to suspendthe article within the outer bag and to maintain a space between thearticle and the outer bag on all sides of the article; and (b) backseals closing the inner web and the outer bag respectively are laterallyoffset from one another.
 11. A packaging machine as claimed in claim 10,wherein the web and the tube are severed across the transverse seals toform discrete packaged articles each suspended within a pressurisedouter bag.
 12. A packaging machine as claimed in claim 10, wherein thefirst station is operative to wrap the web around the articles to formsealed inner pouches.
 13. A packaging machine as claimed in claim 12,wherein within the first station the inner pouches are evacuated orfilled with an inert gas.
 14. A packaging machine as claimed in claim10, wherein a station forms longitudinally extending welded pinches inthe outer bag to impart a cusped cross-section to the outer bag. 15.(canceled)